I know that there are plenty of these out there all attempting to do the same thing, but no, mine is pretty much no different. I made this a couple months ago as a test. Regardless I decided to upload it.
This mod adds guns to minecraft. These gun include, and are limited to:
M4 Carbine with a M203
To reload a gun press r to remove the magazine, then r again to put in a new magazine. If you dont have any full magazines in your inventory just hold out an empty mag in your hand then press r. It should refill the magazine, which can now be used in your gun, unless you dont have any bullet shells in your inventory. Empty bullet shells can be recycled to get full bullet shells. The henry rifle doesnt use magazines, and instead just uses bullet shells to reload. On the M4 Carbine with a M203 attached press x to switch to secondary fire. You will then be able to launch a grenade out of your gun. You can do this once per magazine reload as long you have tnt in your inventory.
For recipes use JEI